Hybrid magnetic apparatus for use in medical applications

Permanent magnet assemblies and hybrid magnetic apparatus are disclosed for use in medical applications, particularly permanent magnet assemblies for use in Magnetic Resonance Imaging (MRI) and/or Magnetic Resonance Therapy (MRT) to produce a volume of substantially uniform magnetic field in a restricted part of the patient's body in a region either adjacent to the surface of one permanent magnet assembly or between a set of a first and second permanent magnet assemblies, leaving open access to the patient's body. The assemblies consist of a plurality of annular concentric magnets spaced-apart along their axis of symmetry. A method for constructing such annular permanent magnetic assemblies is disclosed, using equi-angular segments permanently magnetized. The hybrid magnetic apparatus includes an electromagnet flux generator for generating a first magnetic field in the volume, and permanent magnet assemblies for generating a second magnetic field superimposed on the first magnetic field for providing a substantially homogenous magnetic field having improved magnitude within the volume.